Mechanism for transferring a maximum demand indication from one indicator to anotherindicator when the former is restored to its intial position



Nov. 2l, 1950 R. o. HAMILL 2,531,038

MECHANIsM FCR TRANSFERRINC A MAXIMUM DEMAND INDICATION FROM CNE INDICATOR To ANoTHER INDICATCR WHEN THE FORMER Is REsToRED To ITs INITIAL PosITIoN 2 Sheets-Sheet 1 Filed Jan. 30, 1947 J/vvvvvvvvvvvvvvvvvvwvvvvvvv INVENTCR.

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MECHANISM FOR TRANSFERRING A MAXIMUM DEMAND INDICATION FROM -ONE INDICATOR TO ANOTHER INDICATOR WHEN THE FORMER IS RESTORED T0 ITS INITIAL POSITION Filed Jan. 30, 1947 2 Sheets-Sheet 2 INVENTOR. e 01522773@ BY m/ mw, fg/M Patented Nov. 21, 1950 UNITED STATES PATENT OFFICE MECHANISM FOR TRANSFERRING A MAXI- MUM DEMAND INDICATION FROM ONE IN- DICATOR TO ANOTHER INDICATOR WHEN THE FORMER. IS RESTORED TO ITS INI- TIAL POSITION 3 Claims.

The present invention relates to an improved maximum demand indicator for electric meters and t e like. More specifically, the invention is directed to that type of maximum demand indicater that gives an indication of the maximum demand for the previous month or previous billing period, in addition to the maximum demand for the current month or current billing period. This is advantageous for several reasons. For example, it is advantageous for settling customers disputes as to the amount of the charge based upon maximum demand loads, because the device automatically retains the meter reading in a transposed position upon another dial ior approximately one month after the taking of that reading and the biiling of that maximum demand load. Also, by giving an indication of the vmaaimum demand for the previous month, in addin tion to the maximum demand for the current month, the meter reader is enabled to check the accuracy of the record made for the previous months maximum demand. Also, by having the indicator give an indication of the maximum demand for the previous month, in addition to the maximum demand for the current month, there is practically eliminated the possibility of a reading becoming lost, such as can happen when a meter reader resets the maximum demand indicator before he makes a record of the reading of that indicator.

The general object of the present invention is to provide improved mechanism actuated by the meter reader in the resetting operation for, first, resetting the previous months indicator to zero and then transferring the reading of the current months indicator to this previous months indicater.

One of the features of this improved operating mechanism is that it is entirely positive in its operation, and does not rely upon spring energy, or the like, to reset the previous months indicator to zero, or to transfer the current months reading to the previous months indicator. That is to say, in the performance of the resetting operation, the meter reader is enabled to transmit a positive drive to the previous months indicator for resetting this indicator to Zero7 and he is also enabled to transmit a positive drive for transferring the current months reading to the previous months indicator. This positive drive minimizes or prevents diflculties which are likely to arise in spring actuated devices, because of spring breakage, stiffness of lubrication, corrosion of parts, etc.

Another feature of this improved operating mechanism is that there is nothing critical about the speed at which the meter reader performs the resetting operation. That is to say, the meter reader can rotate the resetting crank at a very rapid rate, or at a very slow rate, Without the possibility of erroneous operation. The above-mentioned positive drive to the two indicator inembers avoids any necessity of having to operate the mechanism at a speed above or below a critical speed. Y

Other features of this improved operating mechanism reside in a ratchet mechanism which holds the current months indicator against advancing motion, While the previous months indicator is being reset to zero; also in a friction slippage clutch which permits this resetting motion of the previous months indicator relatively to said ratchet mechanism; and, furthermore, in an overrunning clutch or one-way drive device which transmits the motion from the current months indicator to the previous months indicator when the current months indicator is being reset to zero. clutch in the operating mechanism, the current months indicator is made completely free of the previous months indicator during the normal operation of the apparatus during the course of the month, so that the mechanism does not impose any frictional load upon the current months. indicator, and hence the apparatus imposes no additional load upon the rotating elements of the electric meter.

Other features, objects and advantages of the invention will appear from the following detailed description of one preferred embodiment of the invention. In the accompanying drawings illustrating such embodiment:

Figure 1 is a front elevational view of this preferred embodiment of my maximum demand apparatus;

Figure 2 is a longitudinal or axial sectional view taken approximately cn tlte plane of the line 2 2 of Figure 1;

Figure 3 is a detailed sectional view taken approximately on the plane of the line 3 3 of Figure 2, showing the resetting crank pin, the resetting arms and resetting sectors;

Figure i is a fragmentary elevational view showing the assembled relation of the resetting pinions, ratchet mechanism, slippage clutch and overrunning clutch;

Figure 5 is a fragmentary transverse sectional view taken approximately on the plane of the line 5-5 of Figure 4, showing the operating re- By virtue of this overrunning.

lation between the ratchet mechanism and the overrunning clutch; and

Figure 6 is a detailed sectional View taken on the plane of the line E3- of Figure 4, showing the motion transmitting pusher connection from the electric meter to the maximum demand indicator.

The assembly illustrated in Figures 1 and 2 is a maximum demand register which can be applied to a conventional watthour meter, or to a thermal type of demand meter, or to any other type of meter device in which it is desired to register maximum demands. The meter itseif is not shown in the drawings, because meter structures of these types are well known to those skilled in the art. The present demand register combines a plurality of spaced supporting plates iii, il, i2 and i3, which are held in spaced relation by suitable spacing posts or sleeves i4 and i5. Secured to the iront side of the front supporting plate i E is a dial plate i6 on which are marked concentric outer and inner circular scales l? and i8 (Figure l). The rst or outer scale i'! reads in a clockwise direction from its zero value to its maximum value, and constitutes the current months maximum demand scale. The second or inner scale i8 reads in the opposite or counter-clockwise direction from its zero value to its maximum value, and constitutes the previous months maximum demand scale. Swinging over the outer scale l'! is a pointer i9 which cooperates with the scale i? for indicating the maximum demand of the current month, or other maximum demand interval being measured. Swinging over the inner scale i8 is a shorter pointer 20 which cooperates with the inner scale for indicating the maximum demand of the previous month, or of such other maximum demand interval as is being indicated by the device. The two pointers I9 and 2d are concentrically mounted for pivotal movement about the same axis, and to accentuate the distinction between the current months demand indication and the previous months demand in dication, the rst scale I'I and first pointer i9 are preferably colored black, and the second scale i8 and second pointer 20 are preferably colored red, it being understood, however, that other contrasting colors may be used. Attention is again directed to the fact that the advancing motion of the irst pointer i9 is in a clockwise direction, whereas the advancing motion of the second pointer 2li is in a counter-clockwise direction, from which it will be seen that when the present months pointer i9 is being reset at the end of the month, its counter-clockwise direction can be imparted to the previous months pointer 2! for causing this latter pointer to move in an advancing direction. This will hereinafter appear in more detail in the subsequent description of the resetting mechanism. Totalizing register dials 22 may be located between the outer and inner arcuate scales at the upper portion of the dial plate for totalizing the accumulative maximum demand over the entire operating period of the meter. These totalizing dials are conventional equipment in maximum demand meters, and form no part of the present invention.

Referring to Figures 2 and 4, the current months demand pointer i9 is secured to a hub 24 which is staked, or otherwise made fast, to a main staff or spindle 25. rihe previous months demand pointer 2B is secured fast to a resetting pinion 2S which. is freely rotatable upon the central shaft 25 directly behind the hub 24. A reduced front end of the central staff or spindle 25 has bearing support in a bearing bushing 2T mounted in an angular bearing bracket 28 which has its lower end secured to the front supporting plate i0 by a screw 2S and associated staking pins. A reduced rear end of the central shaft 25 has bearing support in a bearing bushing 3i which is mounted in the second supporting plate Il.

Motion is transmitted from the electric meter to the above described demand indicator mechanism through the instrumentality of a demand actuated primary element, preferably in the form of a pivotally swinging pusher arm 33 (Figures 4 and 6). This pusher arm is rotatably mounted on a shaft 34 which has its iront end supported in the bearing bushing Si and has its rear end supported in the supporting plate i2. In the case of an integrating watthour or block interval type of meter, this pusher arm 35 will be advanced upscale in a clockwise direction (Figures l and 6) at a rate of speed proportional to the prevailingquantity consumption rate, being returned or reset periodically to zero eve-1y nitee' minutes or every thirty minutes by an automatic interval timing mechanism, as is well kno-wn to those skilled in the art. In the case of a thermal type of demand meter, the pusher arm will be pushed upscale in a clockwise direction to a distance proportional to the maximum demand, as determined by the heat storage capacity of the meter, this pusher arm being then reset at the end of the month or other meter reading interval. This pusher arm has a forwardly bent end which swings through an arcuate slot punched in the supporting plate li (Figure 6). This forwardly projecting end is adapted to engage the left hand edge of a driving arm 33, which is secured fast to a resetting pinion 39, this resetting pinion being in turn staked or otherwise secured fast to the rear end of the central spindle 25. Thus, the pusher arm 323 is always operative to transmit more and more advancing motion to the current months demand pointer i9 through the one way pushing connection established from pusher arm 33 to drive arm 38. From the description thus far, it will be seen that resetting motion can be transmitted to the current months demand pointer I9 through the re setting pinion 3S, and that resetting motion can be transmitted to the previous months demand pointer 2B through the resetting pinion 23.

Mounted on the central spindle 35 between these two resetting pinions 25 and 39 are the aforementioned ratchet mechanism, slippage clutch mechanism and over-running clutch mechanism. The over-running clutch mechanism comprises a clutch housing or ring 4i having a hub portion which is freely rotatable upon the central shaft 25. As shown in Figures 4 and 5, this clutch ring Iii is formed with a cylindrical inner recess 43 in which revolves the clutching spider 64 and over-running clutching elements 45. These over-running clutching elements are in the form of balls or cylinders adapted to have a wedging grip between the interior surface 43 and sloping pockets 43 in the spider 44 when relative motion between the clutch ring 4! and spider e4 is in a direction tending to roll the balls outwardly in their tapered pockets 45. The clutching spider 44 is secured fast to the spindle 25, so that it always rotates directly with the drive arm 38 and current months demand pointer I9. A disc 47 interposed between the resetting pinion 39 and clutching spider 413 serves s. toA retain the over-running balls against lateral displacement from their pockets 46.

Rigidly secured to the outer clutch ring 4I is a ratchet wheel 5I having its ratchet teeth facing in a direction to prevent clockwise rotation of the ratchet wheel and of the clutch ring 4I, as viewed in Figure 5. Engaging in the ratchet teeth 52 of this ratchet wheel is a ratchet pawl 53 which is pivotally supported on any suitable pivot pin 54 set between the supporting plates I0 and II. A tension spring 55 normally holds the nose of the pawl 53 pressed into the ratchet teeth 52. Interpcsed between the ratchet wheel 5I and the resetting pinion 26 is the friction slippage clutch comprising a cupped friction spring 51 having radially extending spider arms which bear against the front side of the ratchet wheel 5I. The central portion of this spring spider abuts outwardly against a washer 58 which is secured fast to the inner end of the resetting pinion 26. It will be seen from the description thus far that when the current months demand pointer IB is advanced upscale in a clockwise direction the inner clutching spider 44 of the over-running clutch will be rotated in a corresponding clockwise direction (Figure 5), so that the balls 45 will remain in the deep ends of the pockets 45 and, hence, will not tend to transmit rotation to the outer housing ring 4I of this overrunning clutch. In addition, clockwise rotation of this outer housing ring 4I is positively prevented by the blocking action of the pawl and ratchet mechanism 5I-53. Hence, this upscale advancing movement of the pointer I9in a clockwise direction is prevented from transmitting any corresponding clockwise rotation to the previous months demand pointer 20, so that all upscale movements of the pointer I9 will always be independent of movement of the pointer 20. It will also-be seen from the description thus far that by virtue of the friction slippage clutch 5I, 51, the the previous months demand pointer can be reset downscale in a clockwise direction to its zero position without causing any corresponding clockwise movement (in an upscale direction) of the current months demand pointer It. The pawl and ratchet mechanism 5 I-53 prevents clockwise rotation of the pointer I9 at this time, and the slippage clutch 5 I ,51 permits the previous months demand pointer 2c to be rotated in a clockwise direction relatively to the powl and ratchet mechanism 5I-53. However, it will also be seen that in the second stage of the resetting operation, when the current months demand pointer I9 is reset downscale in a counter-clockwise direction toward its zero position, such motion will rotate the clutching spider 44 in a counter-clockwise direction and cause the balls 45 to rotate toward the shallow ends of their pockets, into clutching engagement with the outer clutch ring all. This will revolve the ratchet wheel 5I in a counterclockwise direction, and such counter-clockwise rotation will be transmitted through the friction slippage clutch 5I, 51 and hence through resetting pinion 26 to the previous months demand pointer 20 for setting up on the previous -months indicator I8, 20 a reading corresponding with the reading previously existing on the current months demand indicator I1, I9,

Referring now to the resetting mechanism which is actuated by the meter reader at the end of the month, or at the end of such other meter reading intervalA as is customary in that particular locality, attention is particularly directed to Figures 2 and 3, which show a resetting shaft EI spaced considerably from the shaft axis 25 of the indicators, this resetting shaft being preferably below the indicator shaft. Said resetting shaft 6I has bearing support in the two supporting plates I0 and II, and has a manually operable crank 62 secured to its front end on the front side of the dial plate I5. Secured to said Setting shaft, between the plates i@ and II is a disc 64 which has a pin 55 extending entirely through the disc to project frcm opposite sides thereof. The outer surface of each end of the pin deiines a sweep circle 56, indicated in dotted lines in Figure 3. The pin ends t5 in rotating through these sweep circles are adapted to impart outward separating motion to front and rear resetting arms 51 and 58, the front arm G1 lying in front of the resetting disc G4, and the rear arm 58 lying in rear of said disc. These two resetting arms have concentric pivotal mounting for independent pivotal increment upon a common pivot pin 69, which extends between the two supporting plates I0 and II. Fixedly secured to the hub portion of the front resetting arm 51 is a front resetting sector gear 1I, and iixedly secured to the hub portion of the rear resetting arm 5S is a rear resetting sector gear 12. The gear tooth peripheries of these two.sector gears are curved concentrically of the pivot axis 59, and the front sector gear 1I meshes with the resetting pinion 25 and the rear sector gear 12 meshes with the other resetting pinion 353.

In the normal position of the resetting disc 64, the resetting pin 55 occupies substantially the position shown in Figure 3, in which position the two resetting arms t1 and 58 can swing inwardh7 substantially into contact with the resetting shaft 6I. The resetting disc t4 is yieldingly retained in this normal position by an indexing detent comprising a swinging arm 15 swinging about a stationary pivot pin 1E and carrying a detent pin 11 on its lower end adapted to swing into a V- shaped notch 18 formed in the periphery of the disc S4. A tension spring 15 hooked to the upper end of the arm 15 above the pivot 15 tends to swing the indexing pin inwardly into the notch 18. Referring to Figure l, when the resetting disc 54 is in its normal position (shown in Figure 3) the resetting crank 52 stands in a substantially vertical position with an arrow 13 on the crank pointing downwardly into alignment with a Stop marker 8l inscribed 0n the dial plate I6. A direction arrow 82, also inscribed on the dial plate, indicates that the resetting crank is to be rotated in a counter-clockwise direction by the rneter reader.

Referring now to the operation of the device, when the unit is first installed the current months demand pointe-r I9 and the previous months demand pointer 2i! will both occupy the zero positions illustrated in Figure l. These zero positions, and also the maximum positions, or both pointers are dened by the pointers striking the -side edges of the inwardly bent portion of the bearing bracket 28. As the load through the meter acts on the primary actuating element 33, it swings this element to diierent degrees. The initial swinging movement transmits an initial deflection through the drive arm 38 to the current mcnths demand pointer i9 for setting up an initial reading. As later degrees ci movement of the demand actuated primary element 33 exceed previous movements, they successively transmit that additional increment of movement to the drive arm 38 for advancing the pointer I9 in a clockwise direction to successive positions for indicating` the maximum demandup to that instant of time. Meanwhile, the previous months demand pointer has remained in its original position, since the overrunning action of the ball clutch l-QB and the positive blocking action of the ratchet mechanism 5I-53 has prevented motion being transmitted to the pointer ZIJ. Let us assume that the meter readings are taken upon a monthly basis, and that ie current month in which this meter has rst been put into operation is the month of January. We will assume that when the meter reader comes to take a reading of the maximum demand indication during the latter part of J anuaiy or the first part of February, the pointer I9 stands at a maximum demand reading of 8, such being the maximum demand for the month of January. After making the appropriate notation of this maximum demand reading on his record book, the meter reader then rotates the resetting crank 62 in a counterclockwise direction through one complete revolution, so as to bring the arrow it back into registration with the Stop mark 8|. Referring now to Figure 3, during the rst half oi this rotation of the resetting shaft 6I, the iront end of the resetting pin 65 moves through its sweep circle E5 for striking the inner or lower edge of the resetting arm El, in the event that the previous months demand pointer 29 is then indicating a maximum demand reading. However, under the assumed condition of the rst month of operation, there will be no reading on the previous months demand pointer, and, hence, the resetting arm S'i will stand substantially in the position shown in Figure 3 where the resetting pin 65 will clear or just contact this arm, there being no necessity of transmitting any resetting motion to the pointer 2U at this time. During the second half of the revolution of resetting pin G5, the rear end of this pin strikes the inner or upper edge of the resetting arm 63 and starts swinging this arm downwardly and outwardly. The resetting arm is swung down to a position of maximum reset where the sweep circle 66 of the pin 55 is just tangent to the inner edge of the resetting arm, The resulting motion of the rear sector I2 transmits a counter-clockwise rotation to the resetting pinion 39, which is transmitted directly through the central spindle to the current months demand pointer for swinging this pointer downscale in a counter-clockwise direction back to its zero position.

Simultaneously with this angular resetting motion of the current months demand pointer I9, an advancing motion in a counter-clockwise direction of the same angular extent is concurrently transmitted to the previous months demand pointer 20. This follows from the one-way clutching action of the ball clutch Ill-46, the counterclockwise rotation of the clutching spider 44 resulting in the balls rolling outwardly into the constricted ends of the pockets 46, and, hence, transmitting corresponding rotation to the outer clutch ring 4I. This in turn transmits counterclockwise rotation to the ratchet wheel 5I, which is freely permitted by the pawl 53, and such counter-clockwise rotation is transmitted through the friction slippage clutch 5T to the resetting pinion 25 and to the previous months demand pointer 29. By virtue of the fact that this advancing motion which is thus imparted to the pointer 2] is of exactly the samev angular extent as the resetting motion which is imparted to the pointer I9, it will be seen that the pointer 28will be advanced in a counter-clockwise direction with respect to its oppositely readingy scale I8, so that the pointer 20 will come to rest with a maximum reading of 8 on the scale 20 at the same time that the current months pointer I9 comes to rest at the zero marking on its scale I'I. The resetting operation is now complete, and it will be seen that the pointer 20 now establishes a maxlmum demand reading of 8 on the scale I8 as being the maximum demand reading for the month of January. The pointer 213 remains in this position during the entire month of February, or until the next resetting operation is performed. Let us assume that during the month of February the maximum demand established by the pointer I9 on the scale It only reached the value of 5. When the meter reader comes to take his reading and to perform the resetting operation at the end of February, he makes a notation in his record book of the maximum demand reading of "5 for the month of February, and he can also check his previous record against the maximum demand indication of 8 for the month of January. He now performs the resetting operation by rotating the resetting crank 62 through a complete revolution, the same as previously described. At this time, the resetting arm 6l is occupying a position in relatively close proximity to the shaft 6I, because the pointer 2G stands with a reading of "8 on the scale I8. Hence, in the rst half of the rotation of the resetting shaft the front end of the resetting pin 65 will engage` the'under side of the arm Sl and swing this arm upwardly and outwardly, so as to transmit resetting motion through the sector gear II to the front resetting pinion 26. When the resetting arm 61 swings out to a position tangent to the sweep circle 66, the previous months demand pointer 20 has been swung back in a clockwise direction to the Zero position on its scale I5. This clockwise motion of the pointer 2D is prevented from imparting any corresponding clockwise rotation to the pointer I 9 (which might otherwise erroneously carry the pointer I9 beyond its maximum demand reading of 5) by reason of the fact that the pawl and ratchet mechanism 5I-53 prevents this clockwise rotation of the pinion 26 being transmitted through the friction clutch 5T to the ball clutch 4I-46. That is to say, this entire resetting motion of the previous months demand pointer 2D is absorbed as slippage in the friction clutch 5'I, so that no part of this motion can accidentally be transmitted to the current months demand pointer I9. Now that the previous months demand pointer 20 has been reset to its zero position, the continued motion of the resetting pin 65 through the latter halfof its rotation is free to perform the second part of the resetting cycle, namely, that of resetting the current months demand pointer I9-and, simultaneously therewith, carrying the previous months demand pointer 20 in an upscale direction to establish the same reading on its scale I8 that is now being obliterated from the current months scale I7. This operation is the same as described above, i. e., the downward swinging motion of the resetting arm 63 imparting counter--v clockwise rotation to the resetting pinion 39 and central shaft 25 for swinging the current months demand pointer I9 back to its zero position. Concurrently therewith, the ball clutch 4 5 46 establishes clutching engagement for transmitting this counter-clockwise rotation through the ratchet wheel 5I and through the slippage clutch 5l to the resetting pinion 26 and previous months dei mand pointer 20 for causing this pointer 20 to. re-

volve up to a maximum demand reading of on the previous months demand scale i8. Thus, the device has been reset at the end of February, preparatory to setting up a maximum demand reading for the month of March, but the previous months demand pointer .20 now stands in the position of indicating a maximum demand reading of 5 for the previous month of February. Thus, at all times the previous months demand pointer indicates the maximum demand of the preceding month. As previously stated, this is often advantageous for settling customers disputes, and, in addition, it checks the accuracy of the record which has been set down for the previous months reading, and also prevents the possibility of a reading becoming lost because of the performance of a resetting operation before the notation of the reading has been made. This additional apparatus for indicating the previous months demand imposes no additional torque load on the load sensing element of the meter, because the overrunning clutch lll-46 frees such element from the additional apparatus during the normal operation of the device.

'I'he primary utility of the invention is in conjunction with electric meters, but I wish it to be understood that the invention can also be applied to other meters for indicating the maximum demand o1' steam, water, gas oil, air, etc. The use of two scales I1 and I8 of dilferent radii appears to be advantageous, but this arrangement is not essential, because a single set of scale markings might ,be used with the current months digits running upscale in a clockwise direction, and the previous months digits running upscale in a counter-clockwise direction. By the use of ap propriate gearing, the two pointers I9 and 20 might also be arranged to have their upscale and downscale movements each in the same direction.

While I have illustrated and described what I regard to be the preferred embodiments of my invention, nevertheless, it will be understood that such are merely exemplary and that numerous modifications and rearrangements may be made therein without departing from the essence of the invention.

I claim:

l. In maximum demand indicating apparatus, the combination of a iirst indicator for indicating the maximum demand of the current month, a second indicator for indicating the maximum demand of the previous month, a demand actuated primary element for transmitting advancing movement to said first indicator; resetting mechanism comprising pin means manually rotatable along a circular path, two resetting arms located in the path of said pin means in such manner as to be actuated in succession, a sector gear and a cooperating pinion operatively interconnecting the rst operated resetting arm and said second indicator to reset the latter to zero, and an additional sector gear and a cooperating pinion operatively interconnecting the second operated resetting arm and said first indicator to reset the latter to zero; and means operative during the resetting of said first indicator for causing said second indicator to be moved upscale through substantially the same range of movement that said iirst indicator is moved downscale in the resetting of the latter.

2. In maximum demand indicating apparatus, the combination of a first indicator for indicating the maximum demand of the current month, a second indicator for indicating the maximum demand of the previous month, said two indicators moving upscale in opposite directions, a primary element responsive to maximum demand for transmitting advancing movement to said rst indicator, resetting means operative to iirst reset said second indicator to zero and to then reset said iirst indicator to zero, slippage clutch mechanism operatively connected between said first and second indicators, ratchet mechanism cooperating therewith for holding said rst indicator against upscale movement While said second indicator is being reset to zero, and means operative during the resetting of said iirst indicator for causing said second indicator to be moved upscale through substantially the same range of movement that said first indicator is moved downscale in the resetting of the latter.

3. In maximum demand indicating apparatus, the combination of a first indicator for indicating the maximum demand of the current month, a second indicator for indicating the maximum demand of the previous month, said two indicators moving upscale in opposite directions, a primary element responsive to maximum demand for transmitting advancing movement to said rst indicator, resetting means operative to rst reset said second indicator to zero and to then reset said first indicator to zero, slippage clutch mechanism operatively connected between said first and second indicators, ratchet mechanism cooperating therewith for holding said first indicator against upscale movement while said second indicator is being reset to zero, and an over-running clutch operatively connected between said iirst indicator and said slippage clutch and ratchet mechanisms and operative during the resetting of said first indicator for causing said second indicator to be moved upscale through substantially the same range of movement that said first indicator is moved downscale in the resetting of the latter.

RET O. HAMILL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,123,977 Wagner July 19, 1938 2,245,393 Fleischmann June 10, 1941 

